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Ace inhibitors: Captopril, ramipril, enalapril and other ‘pril’ medications

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Use the PharmacoPhoto video ‘flash-card’ series to reinforce your knowledge of drug classes and specific medications.

Thanks for joining us as we try to paint a drug picture of the ace inhibitors captopril enalopril ramipril and other drugs that end in the prio affix our ace inhibitors ace inhibitors are angiotensin converting enzyme inhibitors and captopril enalapril and ramipril are primarily used in the treatment of hypertension and also in congestive heart failure but

They have been found to be useful in many other disorders for instance acute myocardial infarction cardiac failure prevention of cardiac remodelling and a number of kidney disorders including diabetic nephropathy so you’re going to see them a lot and it’s really important that you try to get as clear a picture as possible ace inhibitors effect a complex fluid

And electrolyte system called the renin-angiotensin-aldosterone system and if you can understand the renin-angiotensin-aldosterone system then you’ll really start to understand the ace inhibitors renin is a protein and an enzyme that is secreted from this portion of the kidneys right here the juxtaglomerular apparatus think of renin as being the kidneys way of

Summoning a valuable stress hormone a stress hormone that’s critical in times of low blood pressure and it’s critical in times of dehydration in other words the kidneys are going to secrete renin and that is going to result in a cascade of events that ultimately leads to the orchestration of every mechanism that we have to increase blood pressure and to fight

Against dehydration so firstly the renin is going to be secreted when the kidneys sense a decrease in blood pressure a second reason for renin secretion is the stimulation from the sympathetic nervous system and a final reason for renin release is when the proximal tubular cells decide that there is too little salt in any of those instances we now have renin in

The blood and let’s leave that aside for a second and go over to the liver at the same time that the kidneys were deciding whether to release renin or not to release renin the liver was making and releasing a hormone or a pre hormone called angiotensin no jen we can simplistically look at angiotensin know jen as being way too large to be an effective hormone so

We’re going to have to cleave it two different times in order to make it a super stress hormone and the first time is with renin renin takes this angiotensin no jen and makes it simply angiotensin and then it’s ready to get cleaved one more time and become a stress hormone the way that angiotensin one is going to be cleaved to angiotensin 2 is to come into contact

With angiotensin converting enzyme and angiotensin converting enzyme or ace is released from the lungs and from epithelial cells when the ace it’s the angiotensin one there will be a cleaving to the active angiotensin to our ace inhibitors block most of the production of angiotensin 2 but they’re not going to block all of the production of angiotensin 2 because

There’s some that gets produced by another pathway the actions of angiotensin 2 and therefore what we block with our ace inhibitors are firstly angiotensin 2 directly stimulates the kidneys to hold or keep more water angiotensin 2 binds to the epithelial cells all across the body yielding a direct constriction of the blood vessels it’s a very potent vasoconstrictor

And as a matter of fact eventually the angiotensin ii constriction eventually leads to a lot of the permanent remodeling changes that occur in blood vessels angiotensin 2 also contributes to ventricular remodeling so remodeling of the heart that occurs in congestive heart failure angiotensin 2 binds to the receptors on the adrenal gland yielding the release of

A hormone called aldosterone which we nicknamed the salt saver and as we save more salt at the level of the kidneys we’re going to save more water and therefore the blood pressure will increase angiotensin ii stimulates the pituitary to release adh which is the water saver and adh goes down to the level of the kidneys and saves more water so as you can see by at

Least five different mechanisms the angiotensin ii is going to increase the blood pressure and ace inhibitors will decrease a lot of not all love but a lot of the production of angiotensin 2 so i think it’s probably easiest for us to think of angiotensin 2 as being a stress hormone that is way overused in conditions such as cardiovascular and renal disorders and

The angiotensin ii will actually lead to a lot of the chronic remodeling of the glomerulus and the ventricle and the blood vessel walls which perpetuates those disorders so the ace inhibitors are very valuable not only in hypertension some of the common adverse effects of the ace inhibitors include a chronic dry cough now this chronic dry cough has the possibility

Of being resolved by a couple different medications but if it’s not able to be resolved with the medications it is most likely the person will be put on the angiotensin ii receptor blockers other adverse effects of the ace inhibitors include hypotension and hyperkalemia or increased levels of potassium in the blood and that is actually exacerbated if the person is

Simultaneously on the potassium sparing diuretics another thing that occurs is that in people who are starting to take ace inhibitors they will actually have a decrease in glomerular filtration rate in the first few days and then it kind of levels off now it’s important that during that time in those first few days while the body is kind of simplistically getting

Used to the ace inhibitors that the person doesn’t actually take other drugs that may be damaging to the kidneys simultaneously so so aspirin and non-steroidal anti-inflammatory drugs decrease protect protective prostaglandins in the kidneys and therefore they should be avoided in the first few days and then finally the ace inhibitors are definitely contraindicated in pregnancy

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Ace inhibitors: Captopril, ramipril, enalapril and other 'pril' medications By PharmacoPhoto